1. Field of the Invention
This invention pertains generally to wireless communications and, more particularly, to channel hopping methods for wireless communication networks. The invention also pertains to wireless communication systems.
2. Background Information
Wireless communication networks are an emerging new technology, which allows users to access information and services electronically, regardless of their geographic position.
All nodes in ad-hoc networks are potentially mobile and can be connected dynamically in an arbitrary manner. At least some of the nodes of these networks behave as routers and take part in discovery and maintenance of routes to other nodes in the network. For example, ad-hoc networks are very useful in emergency search-and-rescue operations, meetings or conventions in which persons wish to quickly share information, and in data acquisition operations in inhospitable terrains.
An ad-hoc mobile communication network comprises a plurality of mobile hosts, each of which is able to communicate with its neighboring mobile hosts, which are a single wireless communication away. In such a network, each mobile host acts as a router forwarding packets of information from one mobile host to another. These mobile hosts communicate with each other over a wireless media, typically without any infra-structured (or wired) network component support.
In contrast to wired networks, mesh topology, low rate-wireless personal area network (LR-WPAN) wireless communication networks are intended to be relatively low power, to be self-configuring, and to not require any communication infrastructure (e.g., wires) other than power sources.
In a wireless communication network including a plurality of single-radio wireless slave nodes and a single-radio wireless master node, some or all of the slave nodes may route traffic from other nodes if the latter cannot reach their destination directly, thereby forming a wireless mesh communication network. The master node is in charge, for example, of major coordination, management and communication network creation operations. In some applications, the master node may be the sole sink of the data traffic transferred across the network. The wireless mesh communication network operates in a finite number of channels within a frequency band in which foreign apparatus (e.g., microwave ovens; other wireless communication networks; other wireless apparatus) can operate as well. An example of such a band is the industrial, scientific and medical (ISM) unlicensed radio band.
Interference is a well known problem that is always present when deploying and operating wireless communication networks. Interference originating from foreign apparatus can degrade the data transmission performance and reliability of a wireless communication network. Therefore, it is important to operate in channels that are as free as possible from this foreign interference. Although many known methods of relieving this problem are possible with improved physical and data link layer techniques, the notion of simply moving to a different part of the allocated frequency spectrum (i.e., a different channel) is preferable due to its low-cost implementation.
There is room for improvement in channel hopping methods for wireless communication networks.
There is also room for improvement in wireless communication systems.